Process for preparing imidazolidin-2,4-dione compound and method for acquiring solid state 4,5-dihydroxy-2-imidazolidinone compound

Abstract

An object of the present invention is to provide an industrially suitable process for preparing an imidazolidin-2,4-dione compound which is safe, simple and easy to prepare the imidazolidin-2,4-dione compound with high yield, which is a useful compound, for example, as a material for decomposing a harmful halogenated aromatic hydrocarbon compound such as dioxin, etc., an electroless silver plating solution for electronic parts, or a diazo copying material, etc. This object can be solved by a process for preparing an imidazolidin-2,4-dione compound which comprises subjecting a 4,5-dihydroxy-2-imidazolidinone compound, (1) to dehydration reaction in the presence of an acid catalyst(s); or (2) to reaction at 100 to 300° C. Or, it can be solved by a process for preparing an imidazolidin-2,4-dione compound which comprises reacting a mixed solution of a urea compound, glyoxal, and a base at 20 to 300° C. Also, an object of the present invention is to provide a method for acquiring a 4,5-dihydroxy-2-imidazolidinone from an aqueous solution containing a 4,5-dihydroxy-2-imidazolidinone by a simple and easy method. This object can be solved by a process for acquiring a solid state 4,5-dihydroxy-2-imidazolidinone compound which comprises mixing an organic solvent with an aqueous solution containing a 4,5-dihydroxy-2-imidazolidinone compound, and subjecting the mixture to azeotropic distillation.

1. A process for preparing an imidazolidin-2,4-dione compound represented by the formula (2): 
       
         
           
           
               
               
           
         
         wherein R represents a hydrogen atom or hydrocarbon group, which comprises subjecting a 4,5-dihydroxy-2-imidazolidinone compound represented by the formula (1): 
       
       
         
           
           
               
               
           
         
         wherein R has the same meaning as defined above, to dehydration reaction in the presence of an acid catalyst(s). 
       
     
     
       2. The process according to  claim 1 , wherein the acid catalyst(s) is at least one acid selected from the group consisting of sulfonic acids, hydrogen halides, halogenated carboxylic acids, clay minerals, sulfonic acid type cation exchange resins, fluorinated sulfonic acid resins, silica-alumina and inorganic oxides. 
     
     
       3. The process according to  claim 1  or  2 , wherein an amount of the acid catalyst(s) to be used is 0.01 to 1000 mg based on 1 g of the 4,5-dihydroxy-2-imidazolidinone compound. 
     
     
       4. The process according to  claim 1 , wherein the 4,5-dihydroxy-2-imidazolidinone compound represented by the formula (1) is a material obtained by subjecting a urea compound represented by the formula (3): 
       
         
           
           
               
               
           
         
         wherein R represents a hydrogen atom or hydrocarbon group, 
         and glyoxal to condensation reaction in the presence of a base. 
       
     
     
       5. A process for preparing an imidazolidin-2,4-dione compound represented by the formula (2): 
       
         
           
           
               
               
           
         
         wherein R represents a hydrogen atom or hydrocarbon group, which comprises reacting a mixed solution containing a urea compound represented by the formula (3): 
       
       
         
           
           
               
               
           
         
         wherein R has the same meaning as defined above, 
         glyoxal and a base at 20 to 300° C. 
       
     
     
       6. The method according to  claim 5 , wherein the reaction is carried out after adding the urea compound represented by the formula (3) to a mixed solution of glyoxal and a base. 
     
     
       7. The method according to  claim 6 , wherein the mixed solution of glyoxal and a base is basic. 
     
     
       8. The method according to any one of  claims 5  to  7 , wherein the base is an organic base. 
     
     
       9. The method according to  claim 8 , wherein the reaction is carried out while removing the organic base and water by distillation. 
     
     
       10. A method of acquiring a solid state 4,5-dihydroxy-2-imidazolidinone compound represented by the formula (1): 
       
         
           
           
               
               
           
         
         wherein R represents a hydrogen atom or a hydrocarbon group; 
         which comprises mixing an organic solvent with an aqueous solution containing a 4,5-dihydroxy-2-imidazolidinone compound represented by the formula (1), and subjecting the mixture to azeotropic distillation. 
       
     
     
       11. The acquiring method according to  claim 10 , wherein the aqueous solution containing the 4,5-dihydroxy-2-imidazolidinone compound represented by the formula (1) is an aqueous solution obtained by reacting a urea compound represented by the formula (3): 
       
         
           
           
               
               
           
         
         wherein R represents a hydrogen atom or a hydrocarbon group, 
         and glyoxal in the presence of a base(s). 
       
     
     
       12. The acquiring method according to  claim 11 , wherein the base(s) is an organic amine(s). 
     
     
       13. The acquiring method according to any one of  claims 10  to  12 , wherein the organic solvent forms an azeotropic mixture with water at 1 to 100 kPa and 30 to 130° C. 
     
     
       14. The process according to any one of  claims 1  to  2 , wherein the reaction is carried out at 100° C. to 300° C. 
     
     
       15. The process according to  claim 14 , wherein the reaction is carried out in water at an initial stage of the reaction.